General denies clemency in Manning case

4/14/14 1:26 PM EDT

Turning aside calls for clemency, an Army general has approved the 35-year prison sentence imposed on Pfc. Chelsea Manning for a massive leak of military and diplomatic data to WikiLeaks, the Army announced Monday.

The Army statement said Maj. Gen. Jeffrey Buchanan, the commanding general of the military district of Washington, approved the convictions and the sentence on Thursday.

"His decision to approve the results of the court-martial, which concluded on Aug. 21, 2013, means that no clemency was granted in the case," the Army said. The statement offered no insight into the general's thinking or rationale.

Manning was convicted of sending hundreds of thousands of diplomatic cables and military reports to WikiLeaks in 2010 in what was considered at the time to be the largest leak of classified information in U.S. history.

Col. Denise Lind, the military judge who heard the case instead of the military equivalent of a jury, found Manning guilty on 20 charges but acquitted her of the most serious: aiding the enemy. She imposed the 35-year sentence, the longest ever for a leaker in U.S. history.

Buchanan had the authority to lower the sentence or set aside any or all of the convictions, but he did not do so. An appeal to the Army Court of Criminal Appeals is automatic, the Army said.

A lawyer who recently agreed to represent Manning for the appeals process, Nancy Hollander, said the decision was not a surprise.

"We did not expect any relief" from the convening authority, Hollander said via email, using Buchanan's formal title in connection with the case. "We are going forward with the appeal."